”Actually, there’s no speculation,” market analyst Will Strauss, from Tempe, Ariz.–based Forward Concepts, says of the Hummingbird-iPad claim. ”It’s only the Intrinsity folks who could have taken it up to a gigahertz. Period.”

Strauss, one of a number of industry analysts who have made the case that Hummingbird powers the iPad, points to the fact that X-ray photography and analysis by reverse-engineering firm Chipworks have confirmed that the iPad runs on some version of the single-core A8 processor.

But, Strauss says, an unmodified A8 can clock up to only 650 MHz. Speeding up the A8 further requires the bag of tricks Intrinsity used to make its 1-GHz Hummingbird. Those tricks include shaving off unnecessary instructions in the chip’s core operations and synchronizing the timing of clock cycles to reduce idle time.

Strauss adds that the teardown confirms that the iPad’s mystery CPU was made by Samsung, also the manufacturer of Hummingbird.

Moreover, the iPad’s CPU design appears not to have come from inside Apple, says analyst Linley Gwennap of the Linley Group, in Mountain View, Calif. (Gwennap first blogged about the Hummingbird-iPad possibility in February, soon after the iPad’s specs were announced.) Apple’s chip team came from processor design firm PA Semi, which it acquired in April 2008. Designing a CPU usually takes two to three years—making it unlikely that the PA Semi engineers created the iPad chip in the time they’ve been with Apple.

By contrast, Strauss says, Qualcomm’s ground-up redesign of the A8, Snapdragon, took more than three years and $300 million. ”There’s nothing in the quarterly statements from Apple indicating they spent that kind of money or time,” he says.

So, either Apple placed a big Hummingbird order to make its iPad—and perhaps the next-generation iPhone—or it has quietly bought up Intrinsity to join the PA Semi team as in-house Apple chip designers.

The Intrinsity takeover scenario makes more sense, Gwennap and Strauss say. Intrinsity has lately gone silent, Strauss says, reporting unsuccessful attempts from both the press and industry to make contact with company officials. As of Monday afternoon, Intrinsity’s Web site was off-line, while last week it displayed a generic ”this page under construction” graphic. Intrinsity’s unresponsiveness would make little sense if something like an acquisition weren’t, in fact, under way, he says.

”They launched a proven, successful product,” he adds. ”It’s likely other A8 licensees would want to use the same secret herbs and spices. If they’ve not been acquired, they’d still be hanging their shingle on the door. They were not in financial difficulty, to my knowledge.”

Contacted for more information, an Intrinsity official referred Spectrum to a press spokesman at Apple—who declined to comment.